yes, indeed, the nook tablet only allows users to use 1 gig for non-barnes & noble content. the rest must be dedicated to their stuff. funny thing - i was going to order one of these for myself, and a couple others for family members. now, no way. it would be better if they developed more content and features people really want to spend money on rather than holding consumers who spend their money hostage this way.

i did a search and didn't find this in news, although i can't imagine i'm the first so i probably missed it.

This is not some kind of big secret. It has been clearly mentioned on the Nook Tablet specs page from November 7 on.
As $10 will get you a 8GB micro-sd card, and $20 a 16GB one, this is a non-issue.

There is a very good reason for this partitioning model. All apps have to be installed in the hidden B&N partition. Those interactive books and childrens books are apps that can be 100MB or more in size. The original NC had only 1 GB for apps, and 5 GB for other B&N content and sideloaded content. People were running out of space to install apps. That is why they changed the partitioning model on the NC to 5 GB for all B&N content, and 1 GB for non-B&N content. And that is reason for the partitioning model of the Nook Tablet.

If they would allocate more space for non-B&N content they would limit the amount of B&N content that you could store on the Nook Tablet. With apps (books) of 100MB, and with a rumoured video store coming next year not a good idea, and sure to anger customers.
I do not want B&N to limit the amount of B&N content that can be stored, just because some users do not want to pay $10 for an micro-sd card.